Want to improve your Sprinting? Do these three things.
1/Sprints – Sprint just 30m at maximum speed 6 times with a 3 min rest. warmpup carefully first. Time them precisely and record your progress. Do this session twice a week. With 3 days rest in between.
2/ Bounding- After the 6 sprints have been completed in each session do one of the bounding activities explained at http://www.oztrack.com/blog/2011/04/bounding-training-for-runners-the-oztrack-method/
Make sure you measure these activities and record your progress. Do only a very small volume. Just enough to keep improving each week.
3/ Step Ups – Work at improving your ability to perform step ups just 3 sets of 6 each leg on a low box – keep your lower leg vertical throughout to keep your quad out of it – activate glutes and start each push upward with a stomp and drive upward keeping your left and right hip horizontally level with each other. Aim to lift heavier and aim to make it look easy by being very stable. Do not push the weight up so fast that you get wobbly and unsafe looking. Record all progress and aim to steadily improve. Do this session once a week. Two days before the next sprint session.
Supplement this with variety of conditioning activities that do not leave you tired or sore in anyway for the other three key things in your program. Its crucial that you work at a variety of abdominal and back exercises, arms etc. Vary this steadily and dont get addicted to gym at the expense of the key three sessions outlined above.